ME 388 – Applied
Instrumentation Laboratory
Stirling Cooler Lab
http://www.globalcooling.com/stircoolunit.html
http://www.globalcooling.com/stircoolunit.html
Stirling Cooler Experiment
Thermocouple
Wire Box
Flowmeter
Model 100B
Stirling
Cooler
Variac AutoTransformer
Digital
Power
Meter
Water From
Sink
Variac AutoTransformer
Water To
Sink
Fluke 87
DMM
Fluke 77
DMM
Omega
Temperature
Controller
Thermofoil
Heater
Omega Temperature
Measurement Device
Stirling Cooler Experiment
Laboratory Objectives
• Operating the Global Cooling Model 100B
Stirling Cooler
• Applying Principles of Thermodynamic
• Calculating
–Heat Rejected
–Heat Lifted
–Coefficient of Performance (COP)
Thermodynamics
• Ideal Stirling Cycle:
– Regeneration - Cold
– Expansion - ISO
– Regeneration – Hot
– Compression - ISO
Calculations
Q Lifted
COPR 
W
• Coefficient of
Performance (COP)
Stirling

• Heat Absorbed
• Delivered Power
• Heat Lost??
Q lifted

dT
 mc p
dt


W stirling  Q rejected  Q lifted
Calculations
• Heat Absorbed
• Heat Rejected
Q Lifted  Vvariac I variac  Q lost
 c p Toutlet  Tinlet 
Q Rejected  m
Procedure
•
•
•
•
Setup Data Acquisition
Turn on water and measure average flow
Turn on heat accepter power
Record data until heat accepter
temperature reaches -30 °C
• Turn on heat rejecter power until
equilibrium is reached around -20 °C
• Stop collecting data and turn off equipment
Transient Results
Results
Temp. Time
Cp
dT/dt
(J/kg-K) (K/s)
Heat Lifted
Power
(W)
(W)
COP
COP
(experiment) (Global Cooling)
COP
(C)
(sec)
(Carnot)
0
57
379
-0.23
23.38
10.61
2.2
3.08
13.2
-5
80
378
-0.2
20.59
10.66
1.9
2.85
11.1
-10
107
376
-0.18
17.83
10.7
1.7
2.54
9.2
-23
201
373
-0.11
10.72
10.75
1
2.01
8.3
Results
• Volumetric Flow Rate
• Mass Flow Rate
1.72E-6 m3/sec
1.72E-3 kg/sec
Equilibrium
•
•
•
•
•
Heat Rejected
Heat Lifted
Heat Lost
Power delivered
COP
14.39 W
4.52 W
7.67 W
9.86 W
0.459 @ -21.09 °C
Uncertainties
•
•
•
•
•
•
Time: Wt = 1 s
Volume: Wv = 1ml = 0.000001 m3
Rejector Temp: WTin = WTout = 2C
Current: 0.01 amps
Voltage: 0.01 volts
Stirling Power: 0.1 W
Uncertainty Analysis
Q r   wVc p Tout  Tin 
1
22

2
2
 Q


 Qr

 Q r
r
WQ  
WV   
WTout   
WTin  
r
 V

Tout
Tin







v

V 
t
1
22

2
 V

 V
WV  
Wv   
Wt  
 v

 t
 

Uncertainty Analysis (cont.)
Q L  VI
 Q
L


WQ  
WV
L
 V

2
1
22


 Q L

 

W
I

 I


 
Uncertainty Analysis (cont.)
Q L
COP 
W s




COP
WCOP  
WQ
L
 Q L

1
22


 COP 

 

W

WS 
 W

S

 

2